Silvane is not very strong in the One Power. Her level of strength is described by "The Wheel of Time Companion" as 33(21) which is a middle/low level in Aes Sedai hierarchy.
With this level of strength she is unable to open alone a suitable gateway to Travel.
Particularity of this characterEdit
Silvane Redford is described only in "The Wheel of Time Companion", she is never mentioned in the main books of the Wheel of Time.